1. Technical Field
The invention concerns an oil wiper ring, consisting of a body with one radially external running surface, one inner circumferential surface and an upper and a lower face.
2. Related Art
DE 42 36 641 A discloses an oil wiper ring for internal combustion engines, that is fixed into a groove in a piston, which is moving back and forth within an engine cylinder, and which possesses an outer running surface that is constantly pressed against the cylinder wall by means of the effect of a spring-like expansion device provided within the piston groove, in which the outer running surface is defined by at least two ring-shaped areas (slide ribs) which are concentric, have the same diameter and which are separated by circumferential recesses in the outer wall of the ring, for which purpose each ring-shaped region of the outer sliding surface is inclined upwardly and inwardly, in order to define a conically-shaped surface.
DE 2 324 931 A describes a process and a device for the manufacture of chrome-plated rings for piston grooves. The piston ring for use as an oil wiper ring possesses two circular slide ribs, which have differently shaped geometric structures, and which are provided with a running surface layer.
In JP 9-196172 A an oil wiper ring is described, consisting of a body, which is provided with at least one circular slide rib, wherein the body is located in working contact with a spring element which presses radially outwards. The circular slide ring decreases in diameter in the direction of its free end, and may be provided at its free end with different contours (radii, chamfers or similar).
Within the field of combustion engines, oil wiper rings serve to minimize the oil consumption of an internal combustion engine. As can be seen in the state of the art, a number of design embodiments are known, which are intended to serve this purpose, but which are not always optimally effective.